Biomedical Terahertz Systems

加拿大四分之一的人死于癌症，2015年有8万人死于癌症，皮肤癌尤其普遍。事实上，皮肤癌的发病率相当于所有其他癌症的总和。随着早期发现显著提高存活率，人们对快速、可靠和广泛的皮肤癌检测的需求由来已久。 皮肤癌检测的最新进展是通过近红外波长的光谱分析而出现的。不幸的是，这些波长很难探测到皮下组织并区分良恶性病变。然而，太赫兹(THz)光谱非常适合皮肤癌检测。它可以从其深度太赫兹穿透的皮下探测，并从其对水分的高太赫兹敏感性识别恶性病变。然而，正在开发的肿瘤太赫兹系统存在许多挑战。这些系统昂贵得令人望而却步，对于广泛的临床应用来说太大了，而且数据采集时间长，对体内皮肤扫描无效。这些系统使用传统的太赫兹发射器，这需要昂贵而笨重的钛蓝宝石激光器，并使用传统的太赫兹探测器，通过缓慢的测量技术运行。 拟议的工作将开发具有皮肤癌检测和诊断所需功能的肿瘤学太赫兹系统。这一功能将通过解决与太赫兹发射和检测有关的关键问题来实现。太赫兹发射器将被开发成与廉价和紧凑的掺铒光纤激光器(用于廉价和紧凑的肿瘤太赫兹系统)兼容的发射器。太赫兹探测器将被开发，它利用一种新的技术来实现短数据采集时间。 拟议的工作将使用申请人以前完成的几项试点研究的结果。这些初步研究开发了一种光子纳米喷射透镜技术，该技术将使光导太赫兹发射器和掺铒光纤激光器之间达到所需的兼容性。这些初步研究还开发了一种相位掩模技术，该技术将能够创建具有皮肤癌诊断所需的短数据采集时间的太赫兹探测器。随着这项技术走向商业化和广泛的可获得性/影响，将开发肿瘤学THz系统的原型。正在发展中的肿瘤太赫兹系统具有巨大的医疗和商业潜力。

One quarter of Canadians die from cancer, being 80,000 Canadian deaths in 2015, and skin cancer is especially prevalent. In fact, skin cancer has a rate of occurrence equal to that of all other cancers combined. As early detection dramatically increases survival, there exists a longstanding need for quick, reliable, and widespread skin cancer detection. Recent advances in skin cancer detection have appeared through spectroscopy with near-infrared wavelengths. Unfortunately, these wavelengths struggle to probe subdermally and to distinguish benign and malignant lesions. However, terahertz (THz) spectroscopy is ideally suited to skin cancer detection. It can probe subdermally, from its deep THz penetration, and identify malignant lesions, from its high THz sensitivity to moisture. However, there are many challenges with oncological THz systems under development. These systems are prohibitively expensive, are much too large for widespread clinical use, and have long data acquisition times which are ineffective for in-vivo scanning of skin. These systems use conventional THz emitters, which require expensive and bulky titanium-sapphire lasers, and use conventional THz detectors, which operate through slow measurement techniques. The proposed work will develop oncological THz systems possessing the required functionality for skin cancer detection and diagnostics. This functionality will be achieved by addressing key issues related to THz emission and detection. Terahertz emitters will be developed that are compatible with inexpensive and compact erbium-doped fibre lasers (for inexpensive and compact oncological THz systems). Terahertz detectors will be developed that utilize a novel technique for short data acquisition times. The proposed work will use results from several pilot studies previously completed by the applicant. These pilot studies developed a photonic nanojet lensing technique which will enable the required compatibility between photoconductive THz emitters and erbium-doped fibre lasers. These pilot studies also developed a phase mask technique which will enable the creation of THz detectors with the short data acquisition times required for skin cancer diagnostics. Prototypes of the oncological THz systems will be developed as this technology is moved towards commercialization and widespread availability/impact. The developing oncological THz systems have great medical and commercial potential.